Toyo Seikan Kaisha, Ltd.

Japan Crown Cork Co Ltd.

Shigeru Nagashima

Fumio Mori

Gunji Matsuda

Junichi Itsubo

Kozo Nakamura

Toshihiko Yoshida

A cap adapted for use as a container cover where the cap has a thermoplastic resin liner pressed formed onto the inner surface of a cap shell. The plastic liner is formed such that the difference between the intrasurface orientation index of the outer peripheral portion of the liner and the intrasurface orientation index of the central portion of the liner does not exceed 0.37 where the intrasurface orientation index is defined as the sum of the orientation coefficient of the liner in the radial direction and the orientation coefficient of the liner in the circular direction. A method of making a cap having a thermoplastic liner where the liner is press-formed into shape under conditions whereby the difference between the intrasurface orientation index of the outer peripheral portion of the liner and the orientation index of the central portion of the liner does not exceed 0.37.

Lined closure

Container closure having an easily openable liner, said liner being composed of a composition comprising a base resin consisting of 95 to 30% by weight of a crystalline polyolefin and 5 to 70% by weight of a lowly crystalline or amorphous copolymer of ethylene with otherolefin, a lubricant in an amount of 0.001 to 5% by weight based on said base resin and a polymer containing at least 10% by weight of a conjugated diene in an amount of 1 to 15% by weight based on said base resin. This closure has a good sealing property and an easy openability in combination.

Container closure having easily openable liner comprised of base resin,

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Hiratsuka, Japan

Shigeru Nagashima